A method for manufacturing ceramic matrix composites (CMC) and CMCs made by the method are disclosed. The method can be a manual process or an automated process, such as using a robotic system, that is used for controlled delivery of ceramic particles in a CMC fabric. The method includes identifying voids present between adjacent tows of the CMC fabric and dispensing ceramic particles into the voids. Applying the ceramic particles in the center of the voids reduces the size and volume fraction of the voids/defects, improving the homogeneity of surface texture of the preform, homogeneity of microstructure, and part model shape conformity. The method for manufacturing CMCs creates CMCs having a homogenous distribution of small pores after matrix formation that improves the interlaminar mechanical and thermal properties of the CMCs.

Systems, devices, and methods are provided for manufacturing a carbon ceramic brake disc. Generally, a plurality of uncured or partially-cured bulk molding compound preforms or molding compound layers and ventilation cores are placed in a mold cavity and warm-pressed at a first temperature. The ventilation cores are removed from the resulting cured green body. The cured green body is then removed from the mold, and treated through a polymer infiltration and pyrolysis or reactive melt infiltration process. Certain steps can be repeated until a desired target density or weight is attained.

The present disclosure relates to a porous ceramic media that may include a chemical composition, a phase composition, a total open porosity content of at least about 10 vol. % and not greater than about 70 vol. % as a percentage of the total volume of the ceramic media, and a nitric acid resistance parameter of not greater than about 500 ppm. The chemical composition for the porous ceramic media may include SiO.sub.2, Al.sub.2O.sub.3, an alkali component and a secondary metal oxide component selected from the group consisting of an Fe oxide, a Ti oxide, a Ca oxide, a Mg oxide and combinations thereof. The phase composition may include an amorphous silicate, quartz and mullite.

A silicon carbide flow reactor fluidic module comprises a monolithic closed-porosity silicon carbide body, a tortuous fluid passage extending through the silicon carbide body, the tortuous fluid passage having an interior surface, and one or more thermal control fluid passages also extending through the silicon carbide body, the interior surface having a surface roughness of less than 10 μm Ra. A process for forming such modules is also disclosed.

A method of preparing a woven fabric material for use in a ceramic matrix composite includes passing a desized woven fabric tape having a first inter-filament spacing through a dispersal module configured to transform the desized woven fabric tape into a dispersed woven fabric tape having a second inter-filament spacing greater than the first inter-filament spacing. The dispersal module includes a first charging element with a charged surface and disposed to apply an electric charge to the desized woven fabric tape. The method further includes applying a polymer binder to the dispersed woven fabric tape to create a stabilized woven fabric tape having the second inter-filament spacing.

A method of preparing a woven ceramic fabric for use in a ceramic matrix composite includes transforming a woven fabric sheet having a first tow architecture into a separated woven fabric sheet having a second tow architecture, the first tow architecture including a plurality of warp tows and a plurality of weft tows, and the second tow architecture including a plurality of warp subtows and/or a plurality of weft subtows. Transforming the woven fabric sheet includes separating at least some of the plurality of warp tows and/or the plurality of weft tows into a greater number of corresponding warp subtows and/or weft subtows, respectively, such that second tow architecture includes more warp subtows and/or weft subtows than the first tow architecture comprises warp tows and weft tows, and wherein each of the warp subtows and/or weft subtows includes fewer filaments than corresponding warp tow and/or weft tow. Each of the plurality of warp subtows and/or weft subtows is spaced apart from the closest adjacent warp subtow and/or weft subtow, respectively, a distance of 25 to 230 microns.

A method of preparing a woven fabric material for use in a ceramic matrix composite includes securing a woven fabric tape in tension across a roller, the roller having an outer surface with a plurality of spiked protrusions extending radially therefrom, each of the plurality of spiked protrusions having a diameter between 10 microns and 500 microns. The method further includes passing the woven fabric along the roller, such that the roller rotates with the passing of the woven fabric tape, thereby impinging the spiked protrusions into the woven fabric tape, and separating filaments within tows of the woven fabric tape by penetration of at least one of the spiked protrusions into the woven fabric tape, such that filaments within various tows of the woven fabric tape are pushed apart to form a separated woven fabric tape with a greater number of tows per unit area than the woven fabric tape.

A process comprising: (i) coating particles of silicon carbide, silicon nitride, boron carbide or boron nitride with a metal alloy or metal layer; (ii) agglomerating the particles of step (i); thermally spraying the agglomerated metal or metal alloy coated particles onto a substrate to provide a coating thereon.

The present invention relates to a method for preparing a SiC—Si.sub.3N.sub.4 composite material and a SiC—Si.sub.3N.sub.4 composite material prepared according to same and comprises the steps of: preparing a mold; and forming a SiC—Si.sub.3N.sub.4 composite material by introducing, to the mold, a source gas comprising Si, N and C, at 1100 to 1600° C. More particularly, the present invention provides the SiC—Si.sub.3N.sub.4 composite material of high purity that is applicable to a semiconductor process, and increases the thermal shock strength of a SiC material by causing Si.sub.3N.sub.4, which is a material with a high thermal shock strength, to grow together via a CVD method.

A method to produce a ceramic matrix composite with controlled surface characteristics includes: applying a scrim ply to a surface of a fiber preform, where the fiber preform includes silicon carbide fibers coated with boron nitride; infiltrating the fiber preform and the scrim ply with a slurry, thereby forming an impregnated ply on an impregnated fiber preform; infiltrating the impregnated fiber preform and the impregnated ply with a melt comprising silicon, and then cooling, thereby forming a ceramic matrix composite having a ceramic surface layer thereon, where the ceramic surface layer has a predetermined thickness and is devoid of boron; machining or grit blasting the ceramic surface layer to form an intermediate layer suitable for coating; and depositing an environmental barrier coating on the intermediate layer. Thus, a ceramic matrix composite coated with the environmental barrier coating is formed with the intermediate layer in between.